The primary aim of this project is to evaluate treatment approaches that address the needs of substance-involved female inmates. The objective of this project is to investigate factors surmised to be instrumental in influencing the magnitude of treatment gains, namely: treatment approach, treatment setting, housing type, and individual differences. Simultaneously, this study will apply several comprehensive assessment instruments and strategies to this population, and explore an innovative model of substance abuse assessment and treatment, the Heuristic System. This research is the first systematic empirical evaluation of therapeutic treatment effectiveness of several approaches to treatment for female inmates. Addressing the needs of these women is expected to decrease their vulnerability to future victimization and substance abuse, as well as to reduce their risk to HIV and other serious health problems. A total of 600 incarcerated substance-involved female inmates drawn from Patuxent Institution and the Maryland Correctional Institution for Women will be randomly assigned to one of three treatment approaches: 1) the Heuristic System model, in which individualized treatments are prescribed by assessment data interpreted within the context of a biopsychosocial theory; 2) a Therapeutic Community model, a traditional approach providing all participants with experiences of social emersion, interpersonal confrontation, and shared responsibility; and 3) a Psychoeducational model, stressing the learning of cognitive and social skills. The study will compare the effectiveness of treatment under these models and provide a basis for evaluating whether correctional resources are best invested in specialized treatment-oriented prisons or in dedicated housing units for treatment programs within traditional correctional settings. It is hypothesized that: 1) gains will be higher in the Heuristic System model than in the Therapeutic Community model, which will, in turn, be superior to the cognitive Psychoeducational model; 2) the treatment setting of a treatment-oriented prison will produce more treatment progress than that of a traditional correctional facility; 3) inmates participating in a recovery-oriented cultural milieu will make more gains than who live in the general population; 4) housing type and treatment setting will interact significantly such that treatment is more effective in a dedicated housing unit within a treatment-oriented facility; and 5) in regard to individual differences, subjects with less psychopathology and less severe physical and sexual abuse histories are expected to achieve greater treatment gains than subjects presenting with more severe pretreatment problems.